JPH02185736A - Optical recording disk - Google Patents

Abstract

PURPOSE:To improve heat resistance, workability of production and productivity of the optical recording disk by adding epoxy resin as a chief component, photo- or thermal-cation polymerization initiator and cyclic aliphatic amine into an adhesive. CONSTITUTION:In the stacked structure of the optical recording disks, the adhesive used consists of epoxy resin as the chief component and a hardening agent which contains cyclic aliphatic amine and photo- or thermal-cation polymerization initiator. As the adhesive layer is thermosetting resin, it has heat resistance and prevents cracks from generating in the recording layers 3, 10 and in a protective layer even if the disk is used at high temp. or stored at high temp. The disks can be temporarily adhered with light or heat in the process of stacking, which results in good workability and mass productivity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical recording disk that records, reproduces, or erases information using light.

[Conventional technology]

Conventional optical recording disks have been bonded together using a roll coating method using thermoplastic resin. Moreover, ultraviolet curing resin is used in single-sided optical recording disks.

[Problem to be solved by the invention]

However, in the conventional roll coating method, since the resin used in the roll coating is a thermoplastic resin, it has no heat resistance, and when used or stored at high temperatures, cracks occur in the recording layer and protective layer, making it unusable. It had a point. Is there also a moisture-curing roll coat in which the adhesive layer is a thermosetting resin? This is not practical because the equipment is difficult to handle and there are problems with the reliability (heat resistance, weather resistance) of the bonded optical recording disk. Not on point.

Therefore, the present invention is intended to solve such problems, and its purpose is that since the adhesive layer is a thermosetting resin,
It is heat resistant and will not cause cracks in the recording layer or protective layer even if the optical recording disk is used or stored at high temperatures, and can be temporarily fixed at the bonding stage using light or heat. Therefore, it has excellent workability and is suitable for mass production, and since the adhesive layer can be cured at a relatively low temperature, a double-sided optical recording disk can be easily formed.

[Means to solve the problem]

The present invention provides a bonded structure of an optical recording disk for recording, reproducing, or erasing information using light, which contains at least an epoxy main ingredient and a curing agent, and the curing agent is polymerized with at least a cycloaliphatic amine and a photo or thermal cationic polymer. It is characterized by being bonded together using an adhesive as an initiator.

In the present invention, the amount of silane or metal coupling agent added was 0.5% to 8% of the total weight of the adhesive, but 0.5% to 8% of the total weight of the adhesive.
If it is less than 5%, the adhesion under high temperature and high humidity will be weak, resulting in poor reliability.On the other hand, if it is added more than 8%, weather resistance will be affected by the effects of alcohol, water, and other low molecular weight components caused by the decomposition of the coupling agent. It tends to get worse.

However, this does not mean that it should not be added less than 0.5% or more than 8%, but that it is appropriate to add between 0.5% and 8%. More preferably, the amount added is about 1% to 5%. In addition, in the present invention, the organic peroxide is 0.
It is added in an amount of 1 to 5% by weight, but if it is not added at 0.1%, it takes time to cure the adhesive, and if it is more than 5%, the physical properties of the adhesive tend to deteriorate.

Again, this does not mean that it should not be added less than 0.1% or more than 5%, but that about 0.1% to 5% is appropriate. More preferably, it is added in an amount of 0.5% to 3%.

As the main epoxy agent, one with low viscosity has good workability, so we use bisphenol F type, phenol novolak type, and bisphenol A type epoxy with a small amount of glycidyl ether, diglycidyl ether, etc. added as a monoreactive diluent. Good to use. Since this reactive diluent deteriorates the physical properties of the epoxy after hardening, it is better to limit the amount added, and it is better to keep it at 30% by weight or less.

Examples of cycloaliphatic amines used as epoxy curing agents include 1-isobutyl-2-methylimidazole, 2-ethyl-4(5)-methylimidazole, and 1-benzyl-2-methylimidazole.
2-methylimidazole, 2-methylimidazole, imidazole, 1-cyanoethyl-2-ethyl 4(5)-
It is preferable to use one type or a mixture of two or more FIN selected from methylimidazole, menthanediamine, N-aminomethylpiperazine, N-methylmorpholine, 1,3-diaminocyclohexane, isophoronediamine, and the like.

Among them, menthanediamine and imidazole are preferably used in order to have a relatively long pot life when mixed with the epoxy main ingredient, and the appropriate amount of addition is about 2% to 796%. If it is less than 2%, the curing of the epoxy will be insufficient, and if it is more than 7%, the pot life will be shortened. More preferably 3% to 5% is appropriate.

Examples of coupling agents added to the adhesive in the present invention include γ-(2-aminoethyl)aminopropyltrimethoxysilane, γ-(aminoethyl)aminopropylmethyldimethoxysilane, and γ-methacryloxypropyltrimethoxysilane. Methoxysilane, N-β-(N~ruvinylbenzylaminoethyl-γ-aminopropyltrimethoxysilane,
γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, vinyltriacetoxysilane, γ-anilinopropyltrimethoxysilane, vinyltrimethoxysilane, γ- Chloropropylmethyldimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, vinyltrichlorosilane, vinyltris(βmethoxyethoxy)
Silane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropylmethyljethoxysilane, N-β(aminoethyl)γ-aminopropyltrimethoxysilane, N-phenyl-γ −
Aminopropyltrimethoxysilane, Methyldichlorosilane, Phenyltrichlorosilane, Diphenyldichlorosilane, Tetramethoxysilane, Dimethyldimethoxysilane Phenyltrimethoxysilane, Diphenyldimethoxysilane, Decyltrimethoxysilane, Tetraethoxysilane, Methyltriethoxysilane, Dimethyljetoxysilane Toxysilane, phenyltriethoxysilane, diphenyljethoxysilane, bistrimethylacetamidetrimethylsilylacetamide, bistrimethylsilylurea,
tert-butyldimethylchlorosilane, isopropyl triisostearoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tris(dioctylpyrophosphate) titanate,
Tetraisopropyl bis(dioctyl phosphite) titanate, tetraoctyl bis(ditridecyl phosphite) titanate, tetra(2,2-diallyloxymethyl-1-butyl) bis(ditridecyl) phosphite titanate, bis(dioctyl pyrophosphate) Ethylene titanate, isopropyl trioctanoyl titanate, isopropyl dimethacrylic isostearoyl titanate, isopropyl isostearoyl diacryl titanate, isopropyl tri(dioctyl phosphate) titanate, isopropyl tricumylphenyl titanate, isopropyl tri(N-amidoethyl amidoethyl) titanate, dichloromethane Examples include milphenyloxyacetate titanate, diisostearoylethylene titanate, acetalkoxyaluminum diisopropiate, and the like.

Among these coupling agents, those having a boiling point of 150° C. or higher, such as γ-glycidquibropyltrimethoxysilane and γ-methacryloxypropyltrimethoxysilane, are particularly easy to handle.

Further, examples of organic peroxides added to the adhesive in the present invention include benzoyl peroxide, isononanoyl peroxide, lauroyl peroxide, t-butyl per-2-ethylhexanoate, 1.1- Bis(t-butylperoxy)3.3.5, -trimethylcyclohexane, t-butylperoxyisopropyl carbonate, t-butylperoxybenzoate, methyl ethyl ketone peroxide, t-butyl hydroperoxide,
Examples include dicumyl peroxide, cumene hydroperoxide, di-t-butyl peroxide, and the like. Among these organic peroxides, the half-life temperature is between 60℃ and 100℃.
Examples include benzoyl peroxide, isononanoyl peroxide, and t-butyl peroxide.
-ethylhexanoate, cumene hydroperoxide,
1.1-bis(tert-butylperoxy)3.3
．． 5-) Limethylcyclohexane, etc.

Furthermore, in the present invention, in addition to these additives, there is no problem in adding surfactants, stabilizers, antioxidants, etc. to improve wettability.

〔Example〕

The present invention will be explained in detail below based on the drawings.

FIG. 1 is a basic configuration diagram of an optical disc according to the present invention,
■ and 8 are polycarbonate substrates, 2 and 9 are 5i
AIN layers 3 and 10 are TbFeCo recording layers, 4 and 11 are 5iAIN layers, 5 and 12 are AI reflective films, 6 is an adhesive layer according to the present invention, and 7 and 13 are hard coat layers. The polycarbonate substrates Nos. 1 and 8 were formed with spiral tracking grooves and formatting bit rows at a pitch of 1.6 μm by injection compression molding. The 5iAIN layers 2 and 9 were formed by RF reaction magnetron sputtering using a 5iAl sintered target and introducing a mixed gas of nitrogen and argon.

The TbFeCo recording layers of Nos. 3 and 10 were formed by a DC magnetron sputtering method using a TbFeC0 alloy target and introducing argon gas. Similar to 2 and 9, the 5iAIN layers Nos. 4 and 11 were formed by the RF reaction magnetron sputtering method using a 5iAl sintered target and introducing a mixed gas of nitrogen and argon. Films 5 and 12 were formed by DC magnetron sputtering using an Al metal target and introducing argon gas. After bonding, an ultraviolet curable resin was applied to the disk surface using a spin cord and cured by irradiating ultraviolet rays to form a hard coat.

The adhesive layer according to No. 6 of the present invention will be explained. Dainippon Ink &Chemicals' Evicron S-12 is used as the main agent for epoxy.
9, oil-based shell epoxy Ebicure BMI-12 as an epoxy curing agent, Ciba Geigy's Irgacure 261 as a photo or thermal cationic polymerization initiator, cumene hydroperoxide as an organic peroxide, and a silane coupling agent. γ-glycidoxypropyltrimethoxysilane was used. The pasting method is BMI-12
3, 1 part of Irgacure 261, 1 part of cumene hydroperoxide, 2 parts of γ-glycidoxyprobyltrimethoxysilane, 7% by weight of a hardening agent, and 93 parts of S-129.
% by weight, apply it in a donut shape approximately at the center of the recording radius on the side where the recording layer is formed on one disk, and bond it to the other disk in a vacuum system to complete the system. After leaking and drying the disc in the sun, the disc was irradiated with ultraviolet rays to temporarily fix the disc, and then heated at 60°C for 5 hours to cure it. The disc has a recording layer formed on the outer and inner peripheries and has a seam so that it can be temporarily fixed using ultraviolet light.

Next, in Figure 1, when changing the adhesive layer,
The results of the 3000 hour weathering test at %RH are shown in Table 1.

As can be seen from the results in Table 1, the optical recording disk of the present invention shows no change in properties or pit error rate even after the weather resistance test, indicating that it has long-term reliability. In addition, it can be seen that this embodiment is suitable for mass production because the outer and inner circumferential portions of the disk can be temporarily fixed using ultraviolet rays.

Table 1 Irgacure 261; Ciba Geigy Adekador 5o-120, Asahi Denka It should be noted that the present invention should not be considered limited to these examples, and various changes are possible without departing from the gist of the present invention. For example, in the present invention, a four-layer structure of a ceramic layer, a recording layer, a ceramic layer, and a metal layer is used on a PC board, but there is no problem with a structure in which a three-layer structure of a ceramic layer, a recording layer, and a ceramic layer is bonded together. A single-sided structure may be used in which a ceramic layer, a recording layer, and a ceramic layer are bonded to a PC board on which only one ceramic layer is formed, or a PC board on which no film is formed.

Furthermore, as examples of the ceramic layer, in addition to the 5iAIN layer, a SiN layer, an AIN layer, a 5iAINO layer, etc. may be used, and there is no problem even if the ceramic layers sandwiching the recording layer are made of different materials. In addition to the TbFeCo layer, NdD is used as the recording layer.
In addition to magneto-optical recording layers such as a yFeCo layer and a GdTbFe layer, a Te-TeOx layer, a phase change type such as Te5bAs, and one using an organic dye such as cyanine can also be used. Depending on the type of recording layer, a ceramic layer may not be necessary.

Furthermore, in the present invention, an example was shown in which temporary +Jx bonding was performed using ultraviolet rays, and if an initiator that can be cured by heat is used, temporary fixing is also possible by heat, and curing can be performed using infrared rays, microwaves, high frequencies, etc. I can bring it.

〔Effect of the invention〕

As described above, by adding an epoxy main ingredient, a photo or thermal cationic polymerization initiator, and a cycloaliphatic amine to the adhesive, the workability and productivity of optical media production were significantly improved.

[Brief explanation of the drawing]

FIG. 1 is a basic configuration diagram of the optical recording medium of the present invention. 1.8・・ 219 ・ ・ ３、　　　　　・ 4, 11・ 5, 12・ 6 ・ ・ ・ Sound 7, 13・ polycarbonate substrate 5iAIN layer TbFeCo recording layer 5iAIN layer AI reflective film adhesive layer hard coat layer that's all Applicant: Seiko Epson Corporation

Claims (3)

[Claims] (1) A laminated structure of an optical recording disk that records, reproduces, or erases information using light, which contains at least an epoxy main ingredient and a curing agent, and the curing agent contains at least a cycloaliphatic amine and a light or thermal cation. An optical recording disk characterized in that it is bonded together using an adhesive that is a polymerization initiator. (2) The optical recording disk according to claim 1, wherein 0.5 to 8% by weight of silane or a metal-based coupling agent is added to the adhesive. (3) Add 0.1 to 5% by weight of organic peroxide to the adhesive.
2. The optical recording disk according to claim 1, further comprising: an additive.